Cartridge case



p 3 J. s. HATCHER 1,753,413

7 CARTRIDGE CASE Filed March 9, 1928 ,S 8 !g 5 a 7 WTI 9 HH E A WW 8 \'\YT\T\ W i! c 6 5 a s 7 \mxxxwx awuentoz Julian 5-HE.tEhE1" Patented Apr.

JULIAN S. HATCHER, OF PHILADELPHIA, FENNSYLVANIA CARTRIDGE CASE Application filed March 9, 1928. Serial No. 260,481.

(GRANTED UNDER THE ACT OF MARCH 3. 1883, AS AMENDED APRIL 30, 1928; 370 0. G. 757) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.

The subject of this invention is a cartridge case, more particularly intended for firearms.

The requirements controlling the design of a cartridge were originally based solely on the relationship which was to exist between the cartridge and the chamber of the gun barrel. These requirements consisting of a uniform positioning and a proper support to withstand the blow of the firing pin were admirably fulfilled in the rim type of cartridge. The tendency for the rims of this type of cartridge to interfere with each other when being fed from a magazine or clip led to the introduction and adoption of the rimless type in which the shoulder or forward part of the case is used as a stopping point. Although facilitating feeding from a clip the desirable features of the rim type were sacrificed in that it is difficult to locate a shoulder formed in soft brass with the requisite exactness and the annealing of the neck of the case to prevent spontaneous cracking in storage extending to the shoulder thereby permitting the case to yield forwardly and reducing the effect of the firing pin blow on the primer with the result that hang fires and mis-fires occur.

Because of these diiiiculties the next step in the development was a compromise between the two former types and resulted in the semi-rim cartridge which, however, is found to be productive of jams and malfunctions, especially when feeding in automatic guns.

As a result of this observation I have designed a cartridge which combines the characteristics governing the facility of feeding of the rimless type with the advantages of the loading features of the rim and semi-rim type.

With the foregoing and other objects in view, my invention resides in the novel arrangement and combination of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the invention herein disclosed may be made within the scope of what is claimed without departing from the spirit of the invention.

A practical embodiment of the invention is illustrated in the accompanying drawing. wherein:

Fig. 1 is a View in side elevation showing the arrangement of the improved cartridge when in a clip;

Fig. 2 is a similar view of the rimless type of cartridge;

Fig. 3 is a view of the semi-rim type;

Fig. 4: is a view of the rim type;

Fig. 5 is a detail view of the improved cartridge;

Fig. 6 is a detail view of the improved cartridge shown in the chamber of a gun.

Referring to Figs. 1, 5 and 6 the improved cartridge comprises the customary body portien 5, shoulder portion 6. neck 7, rim or base 8 and cannelure 9 to provide for extraction. Vv hereas the body of the rimless and semi-rim type of cartridges shown respectively in Figs. 2 and 3 is of uniform taper from the shoulder to the cannelure the body of my improved cartridge isofadoubletaper, the forward portion from a to 5 having a greater inclination than the rear portion from b to 0. The inclination of the rear portion may be varied within limits and may be so slight that the rear portion assumes a substantially cylindrical form. The preference for an inclination of the rear portion is due to a facility in extracting.

The rim 8 is of the same size as the semirim cartridge and although it is larger than the rear portion Z c of the body it is no larger than the extended lines of the taper of the forward portion (1-6 as clearly shown in Fig. 5;

By virtue of the foregoing design when the cartridges are in a clip as in Fig. 1 the greater length of their body portions will be in contact to facilitate feeding while the rims will be prevented from interfering. lVhen the cartridge is inserted in the chamber of the barrel as in Fig. 6 the rim will form a stop and provide for ample support to resist the impact of the firing pin. The chamber and the barrel are, of course, shaped to the body of the cartridge.

F or the purpose of comparison the rim type of cartridge is shown in Fig. 4.

I claim:

1. A cartridge case including a substantially cylindrical rear p0rtion,,a tapered forward portion of greater length than the rear portion and a rim the diameter of which is greater than that of the trace of the surface of the rear portion on the planeof the rim 19 and within the trace of the surface of the forward portion on such plane, whereby the rims will be held out of interference when cartridges are stacked side by side and the rim will contact the breech of a gun when the cartridge is inserted in. the cartridge chamoer.

2. A cartridge case including a substantially cylindrical rear portion, a tapered f0rward portion and a rim the diameter of which 20 is greater than that of the trace of the surface of the rear portion on the plane of the rim and within the trace of the surface of the forward portion on such plane, whereby the rims will be held out of interference when cartridges are stacked side by side and the rim will contact the breech of a gun when the cartridge is inserted in the cartridge chamber.

3. A cartridge case including a rim, a body a cannelure between the rim and body, a forward maj or portion of the body being tapered r and affording sole contact when the cartridge rests on a planesurface, and the rim having a diameter in excess of' the body.

4:. A cartridge case including a rim, a body, a forward portion of the body being tapered and affording sole contact when the cartridge rests on a plane surface, and the rim having a diameter in excess of the body, whereby the 4 rims will beheld out of interference when cartridges are stacked side by side and the rim will contact the breech of a gun when the cartridge is inserted in the cartridgechamber. V

5. A cartridge case, including a rim, a. body having a tapered portion terminating forwardly'of the rim, the rim being of greater diameter than the terminal of the tapered portion but within the trace of said tapered portion.

-6. Acartridge case, including a body, a rim greater than any diameter of the'body yet within the trace of the major-forward portion of the body.

7. A cartridge case including a body, a rim'greater than any diameter of the body yet within the trace of the forward portion of the body.

JULIAN S. -HATCHER. 

